The present invention relates generally to multi-station sand mold-making apparatus for producing sand molds for foundry use, and more particularly to a bottom board feeder apparatus for automatically feeding bottom boards onto the tops of mold boxes of varying heights.
Multi-station sand mold-making apparatus have been known heretofore. It is desirable that such apparatus be capable of simultaneously producing the cope (upper half) and drag (lower half) portions of a composite sand mold, the two portions being complete and assembled upon each other and ready for the molten metal pouring operation at the time they leave the apparatus. Typically, a plurality of mold boxes, each containing a mold pattern, are circulated around a closed pathway through a succession of stations at which different mold-making operations are performed.
U.S. Pat. No. 2,049,967 discloses an apparatus in which patterns and mold boxes are circulated around a closed pathway. A mold box is moved along an annular table, the table being indexed so that its rotary movement is intermittent. The mold box is moved through a series of stations at which successive steps in the mold-making operation are performed, the successive steps finally completing the mold and returning the mold box to the starting point to repeat the cycle. At one station a bottom or follow-board is manually placed by an operator on top of a mold box. The turntable is then indexed to a succeeding station at which the mold box is inverted and thereafter supported upon the bottom board.
U.S. Pat. No. Re. 28,735 discloses a similar apparatus in which four pairs of mold box sections of uniform dimensions are repeatedly indexed to move the pairs repeatedly and successively in a circular path through four stations at which different successive mold-making operations are performed. A bottom board is supported on a vertically moving platform which is raised into engagement with the bottom of the mold box prior to stripping the mold. This is in contrast to positioning the bottom board initially on top of the mold box after determining the height of the box and thereafter inverting the assembly to position the bottom board under the box prior to removing the mold from the box.
U.S. Pat. No. 1,304,922 discloses an apparatus in which a bottom board is manually placed on top of a mold box and manually clamped thereto prior to inverting the mold box and withdrawing the pattern.